Catalyst for selective catalytic reduction of nitrogen oxide in moderate/low temperature environment

Abstract

The invention belongs to the field of end gas decontamination of diesel cars, and in particular relates to a MnOx-Wo3 / TiO3 catalyst for selective catalytic reduction of nitrogen oxide, which is used for treating NOx in the end gas of diesel cars in moderate / low temperature environment (120-300 DEG C) and prepared by an immersion method. The catalyst adopts a common metal oxide MnOx as an active component, the raw materials are low-cost and easily obtained, the use condition is simple, and the catalyst can be mass produced. The catalyst disclosed by the invention can be used for catalyzing ammonia selective reduction nitric oxides to be harmless nitrogen and water in the low temperature environment of 120 DEG C, and the high conversion rate of the catalyst can be kept at about 300 DEG C.

Description

technical field [0001] The invention belongs to the field of purification of diesel vehicle exhaust, in particular to a method for treating NO in diesel vehicle exhaust in a medium and low temperature environment (120°C-300°C). x A catalyst for the selective catalytic reduction of nitrogen oxides. Background technique [0002] In recent years, motor vehicle exhaust is one of the most serious sources of pollution. Due to the extensive use of buses and diesel trucks in large cities, the pollution is very serious. According to research reports from international authoritative organizations, among the 150 large cities in the world, Beijing in my country Air pollution in five major cities, Shanghai, Guangzhou, Xi'an, and Shenyang ranks among the top 10. It is urgent to carry out research on diesel engine exhaust purification technology and catalyst development. Exhaust emissions from diesel vehicles are mainly NO x (mainly NO) and soot (PM), CO and HC emissions are significantly...

AI Technical Summary

Problems solved by technology

However, there are still some problems in the practical application of this technology: first, the cost of the catalyst is relatively high; second, vanadium pentoxide itself is a poisonous substance; third, the temperature activity window of the catalyst is narrow. x The conversion rate drops significantly, even less than 50%

For MnO x -TiO 2 Catalytic system with good NO in low temperature range x Conversion rate, but when the temperature exceeds 200 °C, the catalyst will cause NO due to poor thermal stability and sintering x conversion rate drop

Images